Centrifugal pump

ABSTRACT

A centrifugal pump is provided for use with fluids, gases and solids in connection with a drive shaft and a motor. The pump has a split housing and a split impeller mounted on the shaft within the housing. The housing has opposing inlet means on each side of the impeller and a discharge outlet. The impeller can be mounted on a split adapter which comes in various sizes on which the impeller can be mounted for use on various sized shafts.

FIELD OF THE INVENTION

[0001] This invention is generally directed to centrifugal pumps having rotatably driven impellers mounted within a housing so as to create a fluid flow through such housing between an inlet and an outlet therein. More particularly, the invention provides a multipurpose centrifugal pump which can pump clock-wise or counter clock-wise. The pump is provided with adapters so as to utilize with a shaft in marine applications of various sizes.

BACKGROUND OF THE INVENTION

[0002] U.S. Pat. No. 4,688,987 to Ericson et al discloses a centrifugal pump having a split impeller which is mounted directly to an existing drive shaft. The inner surfaces of the hub portions of the split impeller are knurled or otherwise provided with ridges as to bite or lock the hub against the drive shaft when the two portions of the impeller are joined together.

[0003] This prior centrifugal pump is particularly adapted for use in the engine compartment or hull of a marine vessel wherein the impeller is attached for rotation with the drive shaft, such as a propeller drive shaft, and wherein the pump housing is mounted so as to be in a surrounding and spaced relationship to the impeller blades and drive shaft. The impeller is freely rotatable in order to pump fumes or fluids through annular intake openings between the drive shaft and pump housing and deliver the same through an outlet formed in the pump housing.

SUMMARY OF THE INVENTION

[0004] According to the present invention there is provided a self priming multi-purpose centrifugal pump apparatus for use in an atmosphere subject to the build-up of hazardous gases, fluids and slurries or solid objects.

[0005] The apparatus comprises a split housing having a top part and bottom part forming peripheral walls and, fluid inlet openings which surround the power source and provides equal pressure from both sides on a split impeller and a split adapter on which the impeller is mounted. The adapter is provided in a variety of sizes so as to be used with various shafts on which the impeller is mounted. Mounting means is provided for securing the housing so as to be in a fixed, spaced and non-contacting relationship around the drive shaft. The impeller which is sloped on two sides can form a connection of a motor with a drive shaft within and in spaced relationship with the housing. The slope expedites movement of the liquid outward to the vanes. Accordingly, the impeller and housing cooperate to discharge fluids in response to the rotation of the drive shaft without any substantial generation of heat due to friction.

[0006] According to one embodiment of the invention, the split housing, when attached, comprises front, rear, top, bottom and side wall portions, a pair of opposing fluid inlet openings in said side walls of said housing providing equal pressure from both sides on the impeller. The housing is provided with at least two sections which are divided along lines which intersect with the fluid inlet openings. Means is provided for selectively uniting the housing sections.

[0007] A drive shaft according to one embodiment extends through the adapter in spaced non-contacting relationship to the housing so that fluids entering the housing under equal pressure, passes around the drive shaft, along the sloped impeller to the impeller blades to propel the fluid to the outlet opening.

[0008] Preferably, the discharge opening is formed in the top wall of the housing and includes a nozzle means for creating a channel which extends outwardly of the housing.

[0009] Accordingly, to another embodiment, the housing defines a generally cylindrical chamber and the blade means of the impeller substantially extends between the front and rear walls of the housing and outwardly into proximate relationship with the side wall portions thereof.

[0010] The impeller may be adapted to be connected to a motor and a drive shaft or it can connect directly to a motor. The pump may be used by itself to carry fluid from a vessel or container or body of water or can be used in connection with a drive shaft of a propeller for a boat.

[0011] According to another embodiment of the invention, there is provided a fluid immersible self-priming discharge pump for removing a fluid such as water and sludge from a container or vessel or body of water. The discharge pump comprises a motor, a housing associated with the motor having at least two opposing fluid inlet openings which create substantially equal pressure on opposing sides of the impeller. A drive shaft is within the housing and operatively connected for rotation by the motor. An impeller associated with the drive shaft and rotatable within the housing on an adapter so as to draw fluid under equal pressure into the housing through the inlet openings and pass it along the sloped surface so as to discharge the fluid through the outlet openings by means of impeller blades. A hose or nozzle is associated with the outlet opening to carry the discharge fluid away. The means for activating the motor can be in the form of a pump which may be located at a separate area. The motor may be hydraulic or electrical.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 illustrates the mounting of the pump of the invention with the propeller drive shaft and transom of an inboard motor;

[0013]FIG. 2 is an enlarged front plan view of the pump housing taken along lines 2-2 of FIG. 1;

[0014]FIG. 3 is an exploded view of the pump according to the invention;

[0015]FIG. 4 is a view of the pump of FIG. 3 partially assembled

[0016]FIG. 5 illustrates the pump of FIGS. 3 and 4 fully assembled.

[0017] FIGS. 6A-6F illustrate a lining which can be used with the pump of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A more complete understanding of the invention will be had by referring to the following description and claims of a preferred embodiment, taken in conjunction with the accompanying drawings, wherein like reference members refer to similar parts throughout the several views.

[0019] With continued reference to FIGS. 1 and 2 of the drawings, the centrifugal pump 12 according to one embodiment of the present invention, the pump is shown as it is mounted in relationship to a propeller drive shaft 14 within the hull of an inboard motorboat 10 from the propeller 20 through a transom, to the motor or engine 18. A suitable of stuffing box 22,22 can be mounted so as to rotatably support the drive shaft 14 and pump 12. The discharge outlet 23 is attached to a hose 24. It should be noted that although the centrifugal pump 12 is being described for use with the propeller drive shaft of a conventional inboard motorboat 10, the pump 12 could be used in other environments. In addition, although only a single pump 12 is shown in the preferred embodiment, there may be occasions when two or more pumps would be used in the same environment such as a boat having twin screws driven by a pair of parallel drive shafts.

[0020] As shown in FIGS. 3-5 the pump 12 is constructed of a pair of split hemispherically shaped adapters 30A, 30B having lips or ridges 34. An impeller composed of split halves 35A, 35B with blades 36, are joined together by bolts 36 on the split adapters 30A, 30B so as to sit within the lips 34. The bolts 36 go through holes 37 in the impeller halves 30A, 30B into threaded holes 37, 38 to secure the impeller to the adapter. The top portion 40 of the split housing has the discharge opening 23 to which a hose 24 can be attached to carry away the discharge. The top portion 40 can be attached permanently or removably to the bottom portion 41 of the housing. The bottom portion 41 is provided with a drainage port 42 as seen in FIG. 5. The assembled pump 12 has an inlet opening 43 on both sides of the impeller 36. When the housing is assembled it comprises the top, front, rear, and sidewalls of the pump 12.

[0021] In order to create the desired suction and discharge at the inlet and discharge areas of the housing, the impeller blades 36 are constructed to substantially extended outwardly to a point in close proximity with the inner surfaces of the sidewalls. Additionally, the width of the blades 36 is substantially equal but slightly less than the distance between the front and rear walls. The design of the impeller 36 and pump housing is such the upon rotation of a drive shaft, the impeller will simultaneously be rotated to thereby draw air, fumes, liquids, or other fluids inwardly through the opposing inlets. Thereafter, the fluids move along the sloped surface of the impeller 36 to in the outlet nozzle 23 and through the exhaust hose 24 or similar conduit to a point remote from the pump, a slope of 30 to 45 degrees on the impeller is generally suitable for moving fluid to the blades.

[0022] When the engine is activated to rotate the drive shaft, the impeller rotates within the pump housing thereby drawing fluids including liquids and gases through the inlet ports and thereafter discharging the fluids under pressure through the outlet nozzle.

[0023] Therefore, the centrifugal pump of the present invention will automatically function to discharge any hazardous gaseous or fluid buildup or generated due to friction and thus the pump is safe for use in environments where ignitable or combustible fluids or gases are encountered.

[0024] The discharge opening 23 can be tangential, but advantageously it is horizontally aligned with the impeller as seen in FIG. 1. Optionally, the housing may have a stand. Also, the interior of the housing may contain a screen (not shown) to prevent intake of large objects which may damage the impeller. Also, optionally a knife assembly (not shown) may be mounted on a drive shaft to shred or break large particles or unwanted obstructions which are drawn into the pump.

[0025] As illustrated in FIGS. 6A to 6F the pump of the invention 12 with the split top 40 and bottom 41 portions may be provided with a liner 50,52. FIG. 6A shows the liner 50 inserted into the top housing part 40. FIG. 6B is a bottom view of the liner 50 and FIG. 6C is a top view of the liner 60. The liner 50 has an opening 51, which aligns with the discharge opening 23.

[0026] FIGS. 6D-6F illustrate the liner 52 for the bottom part 41 of the housing. FIG. 6D is a bottom view of the liner 52 and FIG. 6E is a top view of the liner 52. FIG. 6F shows liner 52 inserted within bottom part 4. Liners 50 and 51 may be provided with holes so as to be assembled with the top and bottom parts of the housing or they can be adhesively fastened.

[0027] Adapters may be available in several sizes to offer ease of installation. Machining is not required on the impeller, because for various shaft sizes all that is required is that the two-piece adaptor will be sized to confirm to these various shaft sizes. The adapter will space the shaft and the impeller to the adapter when it is tightened down surrounding the adapter, the lips or ridges 34 will offer the added security of not allowing the impeller to slip off of the adapter.

[0028] The adapter and the impeller can be constructed using a variety of materials. The impellers can be produced using a steel mold instead of a sand cast mold, and the impellers can be cast in halve pieces only and can be constructed using a high grade marine aluminum. The impellers which are usually aluminum and the shafts on which they are usually mounted are stainless steel have a major problem with electrolysis if the two components are joined together and are submerged in water for a length of time, the shaft adapter offers a remedy for this problem. The adapter can be constructed with a plastic, for example, delern and it acts as an insulator which in direct effect eliminates electrolysis. The adapter can be also produced in numerous other types of plastics and or inert materials, that can be molded or machined in the form of the adapter.

[0029] The adapter which is used in the mounting of the impeller to a shaft offers some other added bonuses. It produces protection to the shaft by eliminating any risk of electrolysis which was previously stated, it reduces the weight factor added to the shaft, if the impeller is stopped for any reason by a large foreign object entering the blades of the impeller, the shaft will slip on the adapter and will not score the shaft. The impeller when mounted using the adapter can be torque at specific specifications so that when the impeller is stopped by a foreign object the design of the adapter will be sacrificial. The engine, gear box, and shaft will be saved. The adapter will allow the impeller to pump water and if a foreign object enters the blades of the impeller operation of the pump, the impeller will spin on the shaft, allowing an individual to remove the object so the unit may resume its normal operation without having damage incurred to the units, components or the system to which it is attached. The mounting of the impeller to a shaft using the adapter is also beneficial in this respect. Where the center, namely the adapter, is light weight and the exterior component namely, the impeller is aluminum and is heavier, the total unit performs as a flywheel assisting in the balancing of the shaft to which it is attached so as to reduce vibrations.

[0030] The impeller can be constructed using aluminum, and/or injected molded plastic, or glass reinforced plastic. The impeller when cast of aluminum is cast in a steel mold and is cast in ½ sections. This eliminates the cutting of the impeller after casting. The impeller when removed from the mold is generally clean and does not require any machining, just the removal of the fill spout and the drilling and tapping of one hole for the threaded bolt. The finish of the impeller when removed from the mold has a high quality lustrous finish.

[0031] A sloped impeller that is about 26 inches in diameter generally has blades of about 5 inches in width. The pump liner acts as a barrier between abrasives flowing through the pump and the pump housing, reducing wear to the pump housing. Because of the extreme volumes of fluids which the various sized of pumps can pump, the velocity of solid objects suspended in the fluid would be forced against the interior walls of the pump through centrifugal force can cause serious wear to the housing reducing the life expectancy of the pump unit.

[0032] The pump liner can be produced using a variety of materials. The liner which is recommended when the pump is used for rough service would be constructed using a stamped steel form coated with Ceramic or Teflon this would provide excellent wear prevention capabilities, for use in construction, mining, and the oil industry, just to name a few.

[0033] The pump housing can be cast using a sanding cast mold and can be cast using an injected molded system, and can be cast using plastics, and or glass reinforced plastics. The housing surrounds the impeller providing a compartment for the impeller.

[0034] A drainage portal is machined in the lower half of the pump housing. This outlet is required to allow removal of water by gravity flow, when the pump is filled with water and the unit is not functioning, any excess water will flow out of the pump. If there is a risk of freezing temperatures, the water that would have been contained in the pump could possible damage the impeller or other components if the pump is started when the water has frozen, seizing the components. The drainage portal will eliminate this possibility.

[0035] Although the foregoing invention has been described in some detail by the way of illustration and example for purposes of clarity of understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims. 

What is claimed is:
 1. A self-priming centrifugal pump apparatus comprising: a) a split housing having a top and bottom portion forming a front wall, a rear wall and peripheral side walls, a discharge outlet opening in said top portion and inlet means formed by said top and bottom portions, and means for securing said top and bottom portions; b) a sloped split impeller within and in spaced relationship with said housing, said impeller having outwardly extending blades and formed in two parts, and means for securing said two parts together, and c) a split adapter on which said impeller is mounted, said adapter having an opening for receiving a drive shaft, said impeller housing cooperating to discharge fluid through said discharge outlet opening in response to rotation of said impeller.
 2. The centrifugal pump of claim 1 wherein said housing has a pair of aligned fluid inlet means.
 3. The centrifugal pump of claim 1 including a drive shaft extending through a fluid inlet opening and through said adapter in spaced non-contacting relationship with said housing around said drive shaft.
 4. The centrifugal pump of claim 1 wherein said drive shaft includes a propeller.
 5. The centrifugal pump of claim 1 wherein said impeller has a slope on both sides of about 30 to 45 degrees.
 6. The centrifugal pump of claim 1 including a motor associated with said housing and a drive shaft within said housing operatively connected for rotation by said motor, and means for activating said motor.
 7. The centrifugal pump of claim 6 wherein said pump is immersible.
 8. The centrifugal pump of claim 1 wherein said adapter comprises two hemispheres having ridges on its ends and said impeller sits between said ridges.
 9. The centrifugal pump of claim 1 wherein said adapter comprises plastic material.
 10. The centrifugal pump of claim 1 including a drainage port in the bottom portion of said housing.
 11. The centrifugal pump of claim 1 including a lining in said housing.
 12. The centrifugal pump of claim 1 wherein inlet opening on both sides of said impeller create substantially equal pressure on both sides of said impeller.
 13. The centrifugal pump of claim 1 in combination with a drive shaft and a motor.
 14. A self priming centrifugal pump for use with fluids, gases, and solids comprising a drive shaft, a motor means for driving said drive shaft, a split housing having a split impeller mounting on said shaft in spaced relationship within said housing, inlet means in said housing about the shaft so that there is equal pressure on both sides of the impeller, and outlet means for discharging fluids, gases or solids in response to rotation of said impeller. 